Added tool to report entropy per blocksize of file

Added the tool tropy to print entropy per blocksize on given file name. This was based on test.c with some modifications for file input rather than dev random. Name 'tropy' chosen at random in attempts to keep with your style. Also attempted to keep your coding style (or put another way, I have no style). As I was adding a tool I chose to mv tool to tools. Also Updated make file and Readme with information concerning tools.